1. Field of the Invention
The present invention relates to a semiconductor device and a semiconductor package formed by a resin package covering the semiconductor device.
2. Description of the Related Art
The semiconductor device disclosed in Patent Document 1 contains a Schottky barrier diode connected between a source and a drain. In particular, a p-type base layer is formed on a surface portion of an n-type semiconductor layer stacked on an n-type semiconductor substrate of the semiconductor device. A trench is dug from the surface of the n-type semiconductor layer and penetrates through the p-type base layer, and a gate insulating film is formed on the sidewall and the bottom of the trench. A gate electrode is embedded in the trench. An n-type diffusion layer is formed on the surface portion of the p-type base layer.
A trench gate-type transistor is thereby formed in the semiconductor device. In the transistor, the n-type diffusion layer is a source area, and the n-type semiconductor layer is a drain area. A channel is formed near an interface of the p-type base layer and the gate insulating film between the n-type diffusion layer and the n-type semiconductor layer, so that a current passes between the source area and the drain.
A metal layer is stacked on the surface of the n-type semiconductor layer. The metal layer exerts the function of source electrode by means of contacting the n-type diffusion layer and forming the Schottky bonding between the area and the metal layer by means of contacting the area outside the p-type base layer and the surface of the n-type semiconductor layer. In this manner, the transistor and the Schottky barrier diode are formed on one chip in the semiconductor device.
Patent Document 1: Japanese Laid-open Patent Publication No. 2009-59860